What to buy

Hey guys,
I am working on a project for WashU, and we are building a helicopter to fly itself. I want an onboard computer processing flight stability algorithms from various sensors, and I want it to take flight direction commands from a laptop via a radio device.

requirements:
12 x ADC inputs (environment sensors) (including proximity)
4 x PWM outputs (servo control)
1 x I2C data transfer (compass sensor)
1 x support for bluetooth or other radio device

Looking around, Where I come up really short is on the ADC. Are there shields for extra ADC channels? The device needs to be very light weight because its on a cheap helicopter.

What do you suggest? I have been all over SparkFun and Parallax BS trying to find something useful for under $200. The closest ive come is a Basic Stamp with a Toothpick.

Thanks for your help,
-Sean <><

CD4066?

So I should connect
the In of sig A to one sensor reading,
the In of sig B to a second sensor reading and
the outs of A and B to the A0 of the Arduino;

controlling the controlA and controlB with a single digital io pin
where controlA NOT controlB??

so one chip gives me two extra channels? Will I need resistors as well or will this drop in? Have you used this before?

Thank you for your help, and esp for your quick response,
Sean <><

PS. I am referencing http://pdf1.alldatasheet.co.kr/datasheet-pdf/view/26882/TI/CD4066.html

they work OK, check noise specs, etc. id google for circuit examples i dont have one on me.

As ladyada pointed out you can multiplex the ADC inputs. You can also use external ADCs - TI has some that are interfaced via I2C. I’ve also seen SPI and of course the traditional parallel output ADCs.

These options all use external devices, for which there are no shields available commercially. That leaves you either using one (more more) of the protoboard type shields, or designing and fabricating your own PCB.

-j